The invention relates to a complex product containing magnesium, halogen and alkoxy. The invention also relates to a process for the preparation and use of such a complex product. By a complex product is meant either a distinct complex or a mixture of complexes.
To be able to activate magnesium with TiCl4 to produce amorphous MgCl2 for a Ziegler-Natta catalyst, the magnesium has to be brought in a reactive state with respect to TiCl4. This is commonly done in two ways:
1. By forming a complex between MgCl2 and an organic compound having an active hydrogen like an alcohol ROH. This MgCl2.mROH complex is allowed to react with TiCl4. Thereby amorphous MgCl2* is liberated. Equivalent amounts of titanous waste material: TiCl3OR and HCl are formed. This waste material has to be washed away with an excess of TiCl4, which is a disadvantage.
2. By forming a Mg-alcoholate, i.e. Mg(OR)2. This reacts with TiCl4 to give amorphous MgCl2*. An equivalent of waste material, TiCl3OR, is formed also here.
MgR2 is soluble in inert hydrocarbon and reacts with TiCl4 to give amorphous MgCl2* but as MgR2 is a strong reduction agent, an equivalent proportion of TiCl3 is co-precipitated with the MgCl2*. The co-precipitation of TiCl3 is a disadvantage when preparing a high yield polypropylene Ziegler-Natta catalyst.
With Grignard reagents like RMgCl and RMgBr, a strong solvent, i.e. an ether is needed to keep them in solution. If this kind of reagent is reacted with TiCl4, amorphous MgCl2* is formed but at the same time TiCl4 complexates with all the Rxe2x80x94Oxe2x80x94R-oxygen atoms of the ether and a large amount of a catalytically inactive by-product complex R2Oxe2x80x94TiCl4 is formed.
The reagents, reacting with TiCl4 to give amorphous MgCl2* are listed in Table 1. In Table 1, CH denotes hydrocarbon.
According to Coates, G. E., et al., Principles of Organometallic Chemistry, Methuen and Co Ltd, London, 1971, pages 60 and 61, this type of complexes are prepared in diethyl ether, whereby e.g. a dimeric etherate is formed as follows: 
In the equation Me is methyl, Et is ethyl and tert-Bu is tertiary butyl. The etherate is dimeric in both benzene and ether media. The book also mentions that ether-free tert-BuOMgBr is insoluble in hydrocarbons and is likely to be polymeric. Tert-BuOMgCl can be assumed to behave in the same way, i.e. a strong polar solvent like an ether is needed to keep the reaction product in solution.
WO 92/16533 discloses a process for producing alkoxymagnesium halides in a single step by stoichoimetrically reacting magnesium alkyl activated magnesium with an equimolar mixture of an alkyl halogenide and an alcohol. However, in this process an additional equimolar amount of alcohol is added to the reaction media to bring the components into a liquid state in a inert hydrocarbon solution. The achieved solution is thus not RO.Mg.Cl but RO.Mg.Cl.ROH. This solution will in this way contain an equimolar amount of ROH that will react with TiCl4 forming TiCl3OR and HCl in a typical catalyst synthesis where TiCl4 is one of the reaction components.
The same situation can be seen in WO91/05608 where MgCl2 is dissolved in 3ROH to produced MgCl2.3ROH that in turn is brought into contact with Mg(OEt)2 to give an adduct of MgCl2.Mg(OEt)2.3ROH. 1.6ROH is then removed from this adduct by azeotropic evaporation with heptane to give a product of EtO.Mg.Cl.0.7ROH corresponding to the product described in WO92/16533.
WO 91/05608 added toluene and two different alcohols to magnesium chloride and refluxed for a short time. Then, dialkyl magnesium was added and the mixture was further refluxed. A complex of a magnesium haloalkoxide and two alcohols was obtained. Due to the alcohols in the complex, it was not suitable for the activation of TiCl4, see above.
U.S. Pat. No. 4,727,051 reacted MgCl2-ROH complexes and obtained stoichiometric compositions without giving their chemical structure.
When using dissolved magnesium compounds for the activation of the transition metal compound of a Ziegler-Natta procatalyst, such as magnesium chloride, MgCl2, dissolved in a polar solvent, or magnesium alkyl, MgR2 or RMgCl, dissolved in diethyl ether or a hydrocarbon, other problems arise. In the case of MgCl2, problems are caused by the large amount of polar solvent needed for dissolving MgCl2. Evaporation operations of the polar solvent during the process of procatalyst preparation are laborous and, besides, traces of polar solvent on the formed procatalyst has to be removed by separate chemical treatment. In the case of MgR2, if not reacted with TiCl4, a separate chlorination agent and a separate chlorination step is need for activation. In addition to this MgR2 and RMgCl have the drawback that they easily overreduce the transition metal and have to be modified to a less reductive form, e.g. to a magnesium alkoholate Mg(OR)2, before use.
When preparing the procatalyst from starting materials which will react into a final catalytically active complex, i.e. by means of a stoichiometric process, the product generally tends to have unsufficiently Mg and Cl (or other halogen) for satisfactory activity. Thus there is a need for starting materials having an enhanced amount of Mg and Cl (or other halogen) in their molecules.
One purpose of the invention is to provide a soluble magnesium compound, which gives good activity and is soluble in non-polar solvents. The magnesium compound must not overreduce the transition metal, because overreduction leads to low procatalyst activity. Another independent purpose of the invention is to provide a molecule, which contains sufficiently Mg and Cl (or other halogen) to produce high catalytic activity when reacted stoichiometrically with other compounds into a procatalyst or a complete Ziegler-Natta catalyst system.
The above problems have now been eliminated and the purposes fulfilled with a complex product containing magnesium, halogen and alkoxy, essentially characterised by having the following formula (1):
MgpXq(OR)2p-q xe2x80x83xe2x80x83(1) 
wherein X is a halogen, preferably a chlorine, R is an alkyl group having from 1 to 20 carbon atoms, p is from 2 to 20 and q is  less than p, preferably  less than 0.66 p. If there are several halogens X and alkoxy groups OR in the complex product, they can be different or equal.
The complex product according to the invention can, depending on the quality and quantity of elements and groups, be soluble in non-polar organic solvents. Thus, complexes which are both soluble and insoluble in non-polar solvents can be selected among the claimed complexes. The soluble complexes can e.g. be used as starting material for catalytically active stoichiometrical procatalyst complexes and the insoluble complexes can e.g. be used as supporting activators of the transition metal compounds. Further, the complex product of the invention is always less reductive than the above mentioned magnesium alkyls MgR2 and RMgX and is therefore more suitable for activation of the transition metal compound. The complex product has, even at its smallest Mg (p=2) and X (q=1) contents, more magnesium and halogen in its molecule unit than the above mentioned non-reductive Mg(OR)2. Whereas Mg(OR)2 has Mg:X:OR=1:0:2, the claimed complex has at least the ratio M:X:OR=2:1:3.
The chemical structure of the claimed complex product is based on the bivalence and bridge-forming ability of magnesium. It is believed, without limiting the scope of the invention, that the chemical structure is (a): 
wherein each G is the same or different and is selected from said X and said OR to form q units of X and 2p-q units of OR, and p is from 3 to 20. If p/3 is greater than 1 there is in formula (a) a . . . xe2x80x94bridge from the furthest Mgxe2x80x94G to the nearest Mxe2x80x94G of the next unit.
The chemical structure can also be (b): 
wherein each G is the same or different and is selected from said X and said OR to form q units of X and 2p-q units of OR, and p is from 3 to 20, or (c): 
wherein each G is the same or different and is selected from said X and said OR to form q units of X and 2p-q units of OR, and p is from 3 to 20.
Most probably the claimed complex product has the structure of an equilibrium between structures (a), (b) and (c), as illustrated by the following trimer equilibrium of a MgCl2.[Mg(OR)2]2 complex: 
In the above formulas (a1), (a2), (b) and (c), Cl can be replaced by any halogen such as fluorine, chlorine, bromine and iodine, but the purposes of the invention are best fulfilled with chlorine.
The alkyl R of the alkoxy group can be any alkyl suitable for the purpose of the invention. Similar structure and solubility parameter to optional solvents give soluble complexes for stoichiometric preparation of active procatalyst complexes. Different structure and solubility parameters give insoluble complexes for use as activating support. When a solvent having 5-10 carbon atoms, such as toluene, is used, R is preferably an alkyl group having from 1 to 16 carbon atoms, more preferably from 4 to 12 carbon atoms, most preferably from 6 to 10 carbon atoms.
In the above formulas (a1), (a2), (b) and (c), p is chosen depending on the complex product""s purpose of use. A higher oligomer (pxe2x89xa75) is less soluble and is suitable as supporting reagent, whereas e.g. a di-, tri- or tetramer is more soluble and suitable for e.g. homogenous and stoichiometric procatalyst preparation. Generally, p is preferably from 2 or 3 to 20, more preferably from 2 or 3 to 10. For homogenous and stoichoimetric preparation, p is preferably from 2 or 3 to 6, more preferably from 2 or 3 to 4, and most preferably 3.
The number of halogens in the molecule agglomerate of the complex product can vary very much. As was initially established, a large amount of chlorine leads to insolubility in non-polar solvents, whereas good activity requires a large amount of halogen. This means that the amount of halogen has to be balanced. According to one embodiment, q is from 2 to p, preferably 2 (when p is 3).
According to a preferable embodiment of the invention, the formula and structure of the claimed complex product is such that it is soluble in a non-polar solvent, preferably in a hydrocarbon, more preferably in an aromatic hydrocarbon, most preferably in toluene.
Above, the claimed complex product has been described by means of its formula, probable structure and solubility. It is also proper to describe it according to its empirical, i.e. analytical composition. The claimed complex product preferably has the following empirical (Mg=1) composition (2):
MgXa(OR)b xe2x80x83xe2x80x83(2) 
wherein X and R are the same as above, a is 0.4-1.2 and b is 0.8 to 1.6.
According to Rxc3x6mpps Chemie-Lexikon, 7. Ed., Franckh""she Verlagshandlung, W. Keller and Co., Stuttgart, 1973, Band 3, page 1831, a complex is a xe2x80x9cderived name for compounds of higher order, which compounds are formed from moleculesxe2x80x94in contrast to the compounds of first order, in the formation of which atoms participatexe2x80x9d. According to one embodiment of the invention, the claimed complex product is e.g. formed from the molecules MgCl2 and Mg(OR)2 or ROMgCl and Mg(OR)2. For example, it is a complex having a composition corresponding to the following formula (3):
[MgCl2]q/2.[Mg(OR)2]p-q/2 xe2x80x83xe2x80x83(3) 
wherein R, p and q are the same as above. Most preferably q is 2, i.e. it has a composition corresponding to the formula (4):
MgCl2.[Mg(OR)2]2 xe2x80x83xe2x80x83(4) 
wherein R is the same as above.
An important characteristic and feature of the claimed complex product is that it shows a X-ray diffraction pattern having a halo between 14xc2x0 and 26xc2x0 2"THgr", more specifically between 18xc2x0 and 22xc2x0 2"THgr". The halo formation observed in the pattern of MgCl2.[Mg(OR)2]2 separates this complex from Mg(OR)2, MgCl2.2ROH, MgCl2. C6H4(COOR)2 and (MgCl2)2.TiCl4.C6H4(COOR)2 (C6H4(COOR)2 is a typical internal phthalate electron donor), which all have a sharp distinct peak between 5xc2x0 and 10xc2x0 2"THgr", but no halo formation between 18xc2x0 and 22xc2x0 2"THgr".
The invention also relates to a process for the preparation of a complex product containing magnesium, halogen and alkoxy. In the process a magnesium dihalide, an alcohol having from 1 to 20 carbon atoms and a dialkyl magnesium having from 2 to 40 carbon atoms are reacted to form said complex product.
It is preferable in the claimed process, that said magnesium dihalide is magnesium dichloride. Preferably, said alcohol is a compound of the formula ROH wherein R is an alkyl having 1 to 16 carbon atoms, preferably 4 to 12 carbon atoms, most preferably 6 to 10 carbon atoms. Said dialkyl magnesium is a compound of the formula MgRxe2x80x22, wherein each Rxe2x80x2 is the same or different and is an alkyl with 1 to 20 carbon atoms, preferably 2 to 12 carbon atoms, most preferably 4 to 10 carbon atoms.
Said complex product is preferably a complex product according to the above description.
The claimed preparation process preferably has two steps. The process comprises:
a) reacting said magnesium dihalide and said alcohol into an intermediate in liquid form,
b) reacting said intermediate in liquid form with said dialkyl magnesium into said complex.
Without limiting the scope of protection, the process can be described by the following equation:
MgCl2+4ROHxe2x86x92MgCl2.4ROH 
MgCl2.4ROH+2MgRxe2x80x22xe2x86x92MgCl2[Mg(OR)2]2+4Rxe2x80x2H 
In step a) of the two-step process of the invention, said magnesium halide and said alcohol are preferably reacted in a molar ratio of 1:2 to 1:8, more preferably 1:3 to 1:5, most preferably about 1:4. The magnesium halide and the alcohol are preferably reacted at 100 to 200xc2x0 C., most preferably at 110 to 150xc2x0 C. The reaction time between the alcohol and the magnesium halide is preferably 1 to 8 h, most preferably for 2 to 6 h.
According to one embodiment a solvent, preferably a hydrocarbon, more preferably an aromatic hydrocarbon, most preferably toluene, is added to keep said intermediate in liquid form. The amount of solvent is preferably such that said magnesium halide and said solvent are used in a molar ratio of 1:4-1:100, more preferably 1:10-1:40, most preferably 1:12-1:24.
In step b) of the claimed process said magnesium halide and said dialkyl magnesium are preferably used in a molar ratio of 1:1 to 1:4, preferably about 1:2. It is advantageous, if said dialkyl magnesium is provided in the form of a solution, preferably a hydrocarbon solution, most preferably a hydrocarbon solution having a molar ratio between said dialkyl magnesium and the hydrocarbon of said solution of 1:2 to 1:10, preferably 1:4 to 1:8. The hydrogen of said hydrocarbon solution is preferably a hydrocarbon having 5 to 12 carbon atoms, most preferably an aliphatic or aromatic hydrocarbon having 6 to 10 carbon atoms.
According to the product description above, the complex product is preferably soluble so that an active procatalyst complex can be prepared directly by reacting the starting materials with each other. This means, that in the claimed preparation process, said reaction product is recovered in the form of a solution in said solvent or solvents.
According to the initially defined purpose of the invention, the claimed complex product is used for the preparation of an olefin polymerisation catalyst, preferably the transition metal component of an olefin polymerisation catalyst, most preferably the titanium component of an olefin polymerisation catalyst. Naturally, the invention also relates to such a use. More specifically, said complex product is reacted with a titanium compound and preferably with an electron donor compound into said titanium component of an olefin polymerisation catalyst.
As was also initially stated, said complex or a reaction product thereof is according to one embodiment of the invention in liquid form and preferably impregnated on an organic or inorganic catalyst support, more preferably an inert support, even more preferably an inorganic inert support such as silica, alumina, a mixed oxide or mixture thereof, and most preferably silica.
According to another embodiment of the invention, said complex is in the form of an insoluble polymeric complex, acting as Mg provider and catalyst support.